Originally Posted by miked826
"Too tall" would be an understatement. It would not move me on the bike no matter how much gas I gave it. I tossed the jackshaft mount in the trash and ordered a 56T sprocket. I then removed the rear disc brake and am relocating it to the front tire. How good or bad is the Grubee 4G belt drive? That's what I'm looking at now.
Well, I wouldn't toss the jackshaft yet. Looks pretty well built. All you need to do is use a larger sprocket on the jackshaft input, and find the a larger wheel sprocket if possible.
Have you tried the gear calculator in the DIY forum list?